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Folks: Another gap in my education for which I would appreciate some help: First: I have been playing around with my new micrometers (OS and round anvil)and my calipers--in order to learn their use and develop a confidence level. On empty, new Remington brass (.300 win mag)with the little "thingies" (as Hot Core would say  )that I THINK are supposed to be used for measuring the inside diameter of the case neck, and on this new, unfired, unsized brass, I keep coming up with .300 even. Is this normal? Second, let's talk about case-mouth expansion for bullet seating: I am sensitive to the issue of not wanting to deform re-sized case mouths by pulling the expander button back through them--and I know some of you have advised me to use bushing dies to avoid this. But: taking Wood's advice in a previous thread on neck turning, I also ordered an expander body and mandrel of the same manufacturer as the turning mandrel. Here is what I found with my trusty micrometers: the turning mandrel measured .307 and the expander mandrel measured .306--so far so good. BUT, I also measured the expander button out of my Redding FLR die, and it ALSO measures exactly .306. So my question is: what would be wrong with pulling the button out of the FLR die and just relying on the .306 expansion as sufficient to allow me to seat a bullet????? Finally, is there any less danger of PUSHING the case neck out of concentricity (using the expander mandrel) than there is PULLING it out (using the expander button in the FLR die)? Thanks. Russ | ||
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It does not matter what the inside of the case neck measures till its loaded with a bullet, or an expanded as opened it to the correct size.The neck wall thickness is what matters when neck turning. The loaded neck dia. should be under or at maximun saami neck dia. for safety. Most are under by a lot. Normal, i guess. Bushing dies are needed if you are neck turning and not using an expander. I use a Lyman outside neck turner. I flrs first, then turn. I dont see why yours would not work that way, except brass spring back might make you case to tight on the mandrel to turn it. Always best to follow instructions that came with the tool. Go to the Redding Reloading website. Look up Type S full length sizing bushing dies. You will notice you have a choice of using an expander or NOT using an expander. And read on the site about bushing. You have a lot of reading to do. good luck | |||
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Hey Russ, well I'm a little confused. First, to my knowledge, there is not a "thingy" to measure the inside of the case neck. The only 2 ways I know to do it is to use a pin gauge or to measure the neck thickness and subtract the neck brass thickness from the outside diameter. But yes, .300" would be way too small for an inside neck diameter on a 300 win mag. Since you have a bushing die and a neck turner then that would be better than using the expanding mandrel. The reason I say this is that the bushing is supposed to float a little and the expanding mandrel is fixed in place and can push the neck to one side or the other and create runout. One of the big advantage of the Lee Collet Neck Sizer is that the mandrel floats. You can put your hand under the die and move it around. That way the mandrel does not push the neck around and can self center while the collets are being squeezed against the neck on the outside.
Should be about the same chance. With the expander ball or the expanding mandrel, there are no collets on the outside to keep things in line, so if your neck is thicker on one side or exhibits more resistance to being pushed then it will push the neck to one side or the other. I'm kinda guessing here and playing the devil's advocate, but sizing the proper way sounds like the better approach to me. ____________________________________ There are those who would misteach us that to stick in a rut is consistency - and a virtue, and that to climb out of the rut is inconsistency - and a vice. - Mark Twain | Chinese Proverb: When someone shares something of value with you and you benefit from it, you have a moral obligation to share it with others. ___________________________________ | |||
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Thanks, guys. Actually, I do NOT have dies that use a collet or bushing--although I am increasingly feeling the need for that as I get more advie in that direction. Woods: what I was using were the little tips or tits--for lack of a more elegant word--on the other side from the jaws you normally use--say, for measuring case length. You can move the rachet so that they move past each other and one flat part will fit on each side of the inside case mouth--so I would hope I could read the inside diameter from the scale. (But I do understand what .243 is saying. I am just playing with using the tools right now.) I know the calipers are dead on because I can measure something with them and with the ouside 1 inch micrometer, and they are dead on to a half-thousandth. Thanks for the help and sorry I am not describing any of this very well. By the way something went terribly wrong with the expensive Gem indicator on my NECO tool--and I am beginning to think HC may well be right about thingies. Best regards, Russ Russ | |||
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Oh no Russ, you just gave HC a lot of ammo!!   Our only hope for survival now is that HC will somehow miss this post. If he sees that he will never let up! Measuring the inside of the neck with the spreaders on the caliper will not work worth a plug nickel (although HC probably has some kind of use for a plug nickel in the reloading process along with his baling wire and duct tape). To get the inside diameter measure the outside diameter and subtract the total neck thickness (single side thickness x 2). That is exact as long as you are measuring the neck thickness with the micrometer, not the caliper. If you don't have a bushing or collet then get the Lee Collet, it works good. ____________________________________ There are those who would misteach us that to stick in a rut is consistency - and a virtue, and that to climb out of the rut is inconsistency - and a vice. - Mark Twain | Chinese Proverb: When someone shares something of value with you and you benefit from it, you have a moral obligation to share it with others. ___________________________________ | |||
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 Hey Russ, You are doing right well in your descriptions. Calipers have Outside measurement jaws and Inside measurement jaws. You are describing using the Inside jaws. The Pin Gauges that Woods mentioned are indeed more accurate, but for a guy who uses thingys(Woods), if it is within a foot or so it is normally close enough. 
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The expander mandrel is larger than the turning mandrel. It allows for springback in the brass. ________________________ "Every country has the government it deserves." - Joseph de Maistre | |||
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Thanks for the replies, guys--even those of you who are anti-thingy. I was a little surprised that NECO had me go directly to Gem--but I did, and as predicted, things went smooth as silk and they are going to send me a new indicator for my thingy. (Hope no kids are reading this!) I started to mention Hot Core's name to bring a little muscle to bear on them, but I didn't even have to pull that ace out of my sleeve. | |||
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If I may, in my ignorance, offer up my two cents, I have to agree with HC. You're trying to short cut the leaning curve with thingies. It's never been proven to me, if we're talking about anything below bench rest,that pulling an expander ball thru a case neck does any distortion that any other tool wouldn't if it's not used properly. Where you going to neck turn new brass or 1X brass? Why were you going to neck turn? | |||
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stillbeeman: I have no doubt I am getting into this a lot deeper than perhaps I should. I have a couple of custom rifles--one in hand and one on the way--that are supposed to shoot into 1/2 MOA--actions squared, Lilja barrels--that sort of thing. I reloaded years ago for a lot of standard calibers and the only "thingy" I used then was a dial caliper. But I made the mistake of buying the Sierra videos and got all excited. What the hell, I figured--the closer I can come to bench rest capability in the rifle (made by someone else) and the ammo (to be made by me) the better. Never mind that I can't hit a bull in the ass with a shotgun at 12 yards. My main intent was to (1) polish or eliminate the expander button (in order to avoid pulling the neck out of concentricity) and turn the necks--in order for the polished ball or other expander to go through more smoothly--as well as for concentricity. I suspect that old hands like H.C. are chuckling because they think that being a good shot makes up for not measuring runout on your bullet. Russ | |||
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Hey Russ, You taking shooting lessons from Woods?  I did the Neck Turning, Reaming, Water Sorting, and Bullet Weight Sorting stuff until it wore me out. Nothing wrong at all chasing after small groups. Each person needs to decide how much they want to put into the quest. I still fully Prep the Cases, Fire Form but rarely Weight Sort Bullets for centerfires anymore. I do P-FLR the Cases and do not concern myself at all about Run Out. Can't shoot nearly as well as I used to, but it is due to a severe loss of practice time. Maybe this year I can get back into it wide open. I wish you all the best in your quest for Low Run Out. | |||
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The Accurate Reloading Forums THE ACCURATE RELOADING.COM FORUMS Guns, Politics, Gunsmithing & Reloading Reloading Questions re measurement/case mouths
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